We've had much snow this year. As I walked to Mass this morning, I had to walk over large quantities of salt on the streets and in the Church parking lot. That salt had been trampled upon by many people (see Mt 5:13) and was dirty and disgusting. No one would ever consider sprinkling it on their dinner.
Similarly, in the time of Jesus, when conquering armies had vanquished a nation, they spread salt on that nation's croplands and trampled it underfoot to work it deep into the soil. This degraded the soil so that crops planted in that soil would wither and not bear fruit, thus making it unlikely that nation would prosper again.
When we became disciples of Jesus, we received His Word with great joy (Mk 4:16). We became the salt of the earth (Mt 5:13), and this kind of "salt is good" (Lk 14:34). We literally put a "good taste" in the mouth of those who are hungry for God's love. If, however, we fall away from Jesus, we go flat. We become to hurting people that salt which degrades. The enemy has used our "flat" lives to trample people underfoot.
Jesus teaches us: "Salt is good, but if salt loses its flavor what good is it for seasoning? It is fit for neither the soil nor the manure heap; it has to be thrown away. Let him who hears this, heed it" (Lk 14:34-35). "Keep salt in your hearts and you will be at peace with one another" (Mk 9:50).
Every day, draw closer to Jesus. Let Him refresh you with His love. Be salt that refreshes and not salt that degrades.